For each of the resources identified previously [see Resource procurement – part 1] we must incorporate durations for each of the procurement stages.
In the example below, we have task ‘A’. For this task we have identified 3 resource needs as ‘A’, ‘B’ and ‘C’.
These have been categorised into their type as ‘M’ (Material), ‘E’ (Equipment) or ‘L’ (Labour).
The Earliest Start Time (EST) for task ‘A’ is given as project day 81 and we have identified 2 days of Total Float.
That is, it can be delayed by 2 days before it becomes part of the critical path.
In consultation with the suppliers we have given the durations of each of the procurement stages as:
For the first and last stages it is up to the contractor to enter a suitable duration.
The latter, Resource preparation can be used to provide a cushion as needed.
Working back from the task EST we get:
Notice that in this case we find that we should start the procurement process 3 project days before the beginning of the project!
To do this would be a dangerous precedent as approval would not yet be given.
So we have two alternatives. The first is to consider how much total float the task has. In this case we have 2 project days, so we could absorb 2 days but would still need to begin the procurement 1 project day ahead of the official project start.
The other alternative is to extend the project by 3 days. So, if it normally completed on project day 150 it would be project day 153.
The ordering would then begin at day zero and still have 2 days total float.
The above process is then repeated for each resource requirement.
This has to be done separately for each resource because they will each have their own individual peculiarities.
As a history of procurement is built up some aspects will always be the same.
For the case of resource ‘C’ the start day would be 1 day ahead of the project start date.
However, as it has a total float of 4 days we can absorb this within the project and still keep a total float of 3 days.
Where we have concerns about a particular procurement, for example ‘A’ above, we can incorporate a specific task in the main schedule
to monitor this. In this way it remains in focus. This would apply equally to Resource ‘C’ above.
The procurement manager will monitor all of the milestones for each of the resources.
It is easy on a spreadsheet to show completed tasks by colour coding for example.
Also, it is extremely easy to sort these lists by any column, for example by document preparation date, or by type and date etc.
This makes the monitoring exercise that much easier.
For each of the above exercises it is important to think in project days and not ‘calendar’ dates.
Actual calendar dates may change but the project days will not. You must also be aware that a suppliers durations will include weekends and any holidays so make sure that you clarify duration times so that you are both working to the same and not a different schedule.
Under PRINCE2® 2009 planning is covered by the Plans theme.
The purpose of the Plans theme is to facilitate communication and control by defining the means of delivering the products (the where and how, by whom, and estimating the when and how much).
[see Plans - Purpose]
A plan can only show the ultimate feasibility of achieving its objectives when the activities are put together in a schedule
that defines when each activity will be carried out.
[See Plans - The PRINCE2 approach - Prepare the schedule]
PRINCE2 2009 [see ‘The Complete Project Management plus PRINCE2’] describes resource availability.
The number of people who will be available to do the work (or the cost of buying in resources) should be established.
Any specific information should be noted (for example, names, levels of experience, percentage availability, available dates).
[see Plans - The PRINCE2 approach - Prepare the schedule - Assess resource availability]
PRINCE2® is a Registered Trade Mark of the Office of Government Commerce in the United Kingdom and other countries.